Mold for the manufacture of rubber tires.



T. sLbPER.

MOLD FOR THE MANUFACTURE OF RUBBER TIRES.

APPLICATION FILED DEC-15, 1914.

1,147,563. Patented July 20, 1915;

sen

THOMAS SLOPER, 0F DEVIZES, ENGLAND.

meant":

Specification of Letters Patent.

Patented July 20, 1915.;

Application and December 15, 1914. Serial No. eraser).

To all whom it may concern:

Be it known that l, TrroMAs Storm, a subject of the King of England,residing at Devizes, in lViltshire, England, have invented certain newand useful Improvements in Molds for the Manufacture of Rubber Tires, ofwhich the following is a specification.

T his invention is for improvements in or relating to molds for themanufacture of rubber tires and has for its object to provide a moldwhich will be more easy to handle and more effective in operation thanthose heretofore in use.

The invention relates to the type of'mold in. which separable sideplatesare employed to mold the sides of the tire and'the tread is molded bycompression-segments, which, when the mold is together, lie between theside-plates and are thrust forward by. bolts carried in a surroundingthrust-ring so that the rubber to be molded is compressed between aninternal former, the outer sideplates, and the compression-segments.

= According to the present invention, there is employed with thethrust-ring and compressionsegments of a tire-mold of the typedescribed, means which connect the segments to the thrust-ring butpermit of their being.

advanced by the adjusting-bolts. The con-- meeting-means may take theform of one or more bolts for each segment which extends through thethrust-ring and screwed into the segment. The head of the bolt pre ventsthe segment from being detached from the thrust-ring, but permitsalimited amount. of movement to and from the ring. If desired, aspringmay be inserted between the said head and the thrust-ring so thatthe segment is drawn back to the thrust-ring when the adjusting-boltsare released.

The invention also relates to other details hereinafter fully describedand the novel features pointed out in the claims.

In the accompanying drawings :Figure 1 is a transverse section throughpart of a mold constructed according to the present invention; Fig. 2.is a side-elevation ofpart of the circumferential ring and segmentalmembers shown in Fig. .1, and 3 is a section through part of a moldaccording to another method of carrying out this invention.

The same letters: indicate the same parts throughout the drawings.

The tire to be molded is built up on a former A, such as is commonlyemployed with molds for tires, and side-plates B, which may be annular,are placed on each slde of the former and thrust toward each other vtocompress the rubber on the sides of the former. .VVith these parts ithas been proposed to employ a ring built up of segments U to fill in thespace between the v plates B, and the plates have been channeled toreceive the edges of the segments. In the drawings, the plates B arechanneled at B to receive lateral projections C on the segments C,-thechannels and projections being both conveniently beveled so as to in-'sure that the segments will be brought into proper position Whentheplates are clamped forcibly together. All these parts are wellknown andit has before been. proposed to hold segments similar to the segments Gin position by an outer thrust-ring D provided with thrust-screws Thepresent invention, however, relates to the permanent connection of thesegments C, which constitute a transversely divided ring, with thethrustring D. For this purpose, each segment has screwed into it'a-t a.point about midway of its length, a bolt 01' pin E which passes freelythrough a radial orifice D in the ring D and is surrounded by a spring EOne end of this spring bears against the head of the bolt which standsout beyond the ring D, and.the other end; of the spring bears-againstthe bottom of a recess D in the outer face of the ring D.

Screwed into the ring D at intervals are adjusting-bolts F which projectthrough the ring and bear against the segments C, a bolt being providednear the end of each segment.

- In' addition to the segments being permanently secured to the ring D,they are preferably guidhd by the ring so that they cannot becomedisplaced laterally relatively thereto. This guiding is effected by anan nular tongue D on the inner face of the ring D, which tongue entersa-channel G on the outer face of the segments.

It will be appreciated that there isconsiderable advantage in having thecompres-' s de-plates or rings B that the lateral projec- 4 ments.

tions C on thesegments will find their way into the grooves B when theplates are drawn together; the engaging parts B? and C are beveled soclamping the plate together centers the segments C.

l'n use, the segmental rings C are advanced by the adjustingbolts- F sothat the rubber is compressed between them and the final registration oithe segments is edected, as already indicated, by clamping up 'theside-plates. In removing he segments, the bolts F are'slacked and thespring E holds each segment'back toward the thrust-ring D after it isreleased from the tire, so that the thrust-ring with the segments canthen be easily removed.

It is obvious that prior to advancing the segments C to heir properfinal position, gaps occur between the ends of the same. lhese may becovered by introducing a soft metal band between the inner' faces of thesegments and the tire, for example, an endless lead ring which is ofsuch diameter as to .iit within the segments when drawn back towardsthethrust-ring, gives good results thisdoes not prevent the proper advanceof the segments but adapts itself to the smaller circle formed when thesegments are closed up. In Fig. 2, however, means are shown for closingup the gaps which do not require renewing from time to time as with thelead bands and do not constitute a separate detached element. Such meanscomprise a T piece G placed between the adjacent ends of each twosegments. The ends of the segments are recessed atG to receive the T-piece, and the T-piece is held in place by a pin G which passes throughthe stem of the T and enters recesses in the ends of the segthe segmentsis of such dimensions that when the segments are closed up the T- piecefills the recess, but when they are drawn back aspace is left betweeneach side of the recess and the T-piece, as shown in Fig. :2; the headof the T overlapping the segments, however,- prevents rubber from undulyspewing through the gap between the segments, as will be readilyunderstood.

is not essential for the segments C to have lateral. projections Cbeveled on each side to engage correspondingly shaped grooves in theside-plates B. In Fig. 3, segmental sections H are shown, which are provided with a square face on the inner side, and the plates 5 arecorrespondingly shaped to fit them. part which projects beyond thelateral projections H of the segments H. on the outer side of thesegments, so that with this arrangement the segments may be adjustedaccurately by the bolts H when the side-plates J are partly bolted upand then .the can be finally bolted home.

The inner face of the segments C or H plates 3 tire.

The recess formed in the ends of The plates, however, have no,

BEST

may be shaped to mold any desired pattern on the tread, well as to giveit its general shape, orif a soft metal band is employed as describedabove, this may be shaped to produce the required pattern on'the tread.ll here a. lead band is employed the seg; ments C or 11 may be channeledon the in nor face as shown at C", liigs. l and 2. ln these figures alead band K is shown. This band in. addition tobridging the gaps betweenthe seg'nents is perforated to receive studs l? which are t6 be embeddedin the The use of a. lead band to hold studs in this manner is known,and in itself constitutes no part of the present invention, but thesegments being carried by the ring and adjustable by the bolts Fconstitute a. convenient means for holding the lead band in place andpositioning it properly relatively to the side-plates B or J. i 7

Obviously the lateral projections H need not be beveled on the innerface, but in whatever way they a e shaped, the corresponding buttingportions of the plates 8 must also be shaped, for example they maysquare as shown in Fig. 3. v The springs E may be omitted from the boltsE if desired, and the segments merely pulled back by hand after slacking'Lne bolts F.

lVha-t I claim as my invention and desire to secure by Letters Patentis 1. In a mold for manufacturing rubber tires, the combination ofseparable side plates for molding the sides of the tire, a ring dividedtransversely into a. series of compression-segments situated between theside-plates to mold the tread of the tire, a thrust-ring surrounding thedivided-ring, adjusting means operating between the thrust-ring and eachcompression-segment of the divided. rin to advance or withdraw suchsegments relatively to the thrust-ring, and means which permanentlyconnect the segments of the divided'ring to the thrust ring withoutinterfering with such adj usting movement, substantially as set forth.

'2. In a mold for manufacturing rubber tires, the combination ofseparable side plates for molding the sides of the tire, a ring dividedtransversely into a series of compression-segments situated between theside-plates to mold the tread of the tire. a thrustqing surrounding thedivided-ring, adjusting means operating between the tl'irust-ring andeach compression-segment of the divided-ring to advance or withdraw suchsegments relatively to the thrust-ring, means which permanently connectthe segments of the divided-ringto the thrust-ring without interferingwith such adjusting movement, one of these parts (that is thethrust-ring or the divided-ring) being provided with guiding means toretain the two parts in alineinent with each otherduring the adjustingmovement of the segments,

substantially as set forth.

3. In a mold for manufacturing rubber.

tires, the combination of, separable sideplates for molding the sides ofthe tire, a ring divided transversely into a series ofcompression-segments situated between the sideplates to mold the treadof the tire, a thrust-ring surrounding the divided-ring, adjusting meansoperating between the thrustu-ing and each compression-segment of thedivided-ring to advance or withdraw such segments relatively to thethrust-ring, and means which permanently connect the segments of thedivided-ring to the thrustring without interfering with such adjustingmovement, one of these parts (that is the thrust-ring or thedivided-ring) having a peripheral tongue (D and the other a peripheralchannel (G which tongue and channel engage with each other so that thesegments are 'uided in their adjusting movements relative y tothethrust-ring, substantially as set forth.

It. In a mold for manufacturing rubber substantially as set forth.

5. In a mold for manufacturing rubber tires, the combination of,separable side-- plates for molding the sides of the tire, a ringdivlded transversely 1nto a series of compression-segments situatedbetween the side-plates to mold the tread of the tire,'a

thrust-ring surrounding the divided-ring, adjusting means operatingbetween the thrust-ring and each compression segment of the divided-ringto advance or withdraw such segments relatively to the thrust-ring,

means which permanently connect the segments of the d1vided-r1ng to thethrust-ring without interfering with such adjusting movement, each ofthe segments having at its end a recess in that face wh1ch- 1s towardthe tread and extending across the whole face corresponding to thetread, and independent Y bridging-pieces mounted one in each pair ofadjacent recesses to overlap the segments and cover the gaps betweenadjacent segments, substantially as set forth.

= '6. In, a mold for manufacturing rubber tires, the combination of,separable sideplates' for molding the sides of the tires, a ring dividedtransversely into a series of compression-segments situated between theside-plates to mold the tread of the tire, a thrust-ring surrounding thedivided-ring, adjusting-means operating between the thrust-ring and eachcompression segment of the divided-ring to advance or withdraw suchsegments relatively to'the thrust-ring, means which permanently connectthe segments of the divided-ringto the thrust-ring without interferingwith such adjusting' movement, each of the Segments having at its end astepped recess (G in that face which is toward the tread, the largerportion of the recess extending across the whole face corresponding tothe tread, independent T- shaped bridging-pieces (G) mounted one in eachpair of adjacent recesses, and means (G to hold each T-piece in positionso that its T-head overlaps the segments and covers the gaps betweenadjacent segments, substantially as set forth.

.,7. In a mold for manufacturing rubber tires, the combination of,iseparable side plates for molding the sides of thetire, a ring dividedtransversely i to a series of compression-segments situated between'theside-plates to mold the tread of the tire, a thrust-ring surrounding thedivided-ring, adjusting means operating between the thrust-ring and eachcompressionsegment of the'divided-rin'g to advance or withdraw suchsegments relatively to the thrust-ring, radial pins (E) on the outerperiphery of the divided-ring which extend through holes in thethrust-ring, and yielding means (E operating between the pins andthrust-rin'gb which means always 'tends to draw the seg-i ments of thedivided-ring toward the thrustring, substantially as set forth.

8. In a mold for manufacturing rubber i tires, the combination of,separable side 1 plates for molding the sides of the tire, a

ring divided transversely into a series of compression-segments situatedbetween the side-plates to mold the tread of the tire, a

thrust-ring surrounding the divided-ring, adjusting means operatingbetween the thrust-ring and each compression-segment ofthe divided-ringto advance or withdraw such segments. relatively to the. thrust-ring,and means which permanently connect the segments of the divided-ring tothe thrustrlng wlthout interfering w1th such ad ust-1 ing movement, thethrust-ring having a channel on that face which is toward the tread toreceive a so ft metal band, substantially as setv forth. a

9. In a mold for manufacturing rubber tires, the combination of,separable sideplates for molding. the sides of the tire, a

ring divided transversely into a series of "compression-segmentssituated between the sideplates to mold the tread of the tire,'a

thrust-ring surrounding the divided-ring, adjusting means operatingbetween the thrust-ring and each compression-segment of the divided-ringto advance or Withdraw such segments relatively to the thrust-ring, andmeans which permanently connect the segments of the divided-ring to thethrust fingkvitliout interfering with such adjusting movement, the sidesof the divided-ring and the opposed faces of the side-plates be ingprovided one with a tongue and the other with a eeii 'iereting groove,the ceiiperating parts being beveled so that as the plates areforcecltogether the divided-ring will be centered, substantially as setforth.

In testimony whereof I have signed my name to this specification in. thepresence of two subscribing Witnesses.

THOMAS SLOPE.

VVitnesees HAROLD Pnnsons, W. L. AvnnnL.

